Tractor Beams on Enterprise-D

[Kobayshi Maru]

Indeed... I don't think these tractor beams are mighty pieces of hardware at all. They just achieve mighty things!

A tiny runabout was able to tractor the biggest Cardassian warship in "Emissary". So it's not the output power of the towing ship that matters, at least not much. The wimpy Wesley was able to lift a chair with his beam; his arms clearly didn't have to support the weight. So it's not the propulsive power of the towing ship that matters, either. Applying a tractor beam is halfway like lashing in a steel cable. Once it's done, it's done, and keeping the hold requires no application of power. But the other half is different: once you have the enemy attached to your cable, no amount of pulling will budge either him or you, and you don't have to apply any power to fight a tug-of-war.

It's basically a "paralysis beam" or "a pair of concrete boots" in that respect, solidly anchoring you both to "the fabric of spacetime" or something, not merely to each other. Except that it also allows you to tow the enemy along - but possibly this is effortless only when the enemy isn't resisting? The evidence of utterly effortless tractoring comes from standstill scenarios (standstill apparently being a meaningful concept in the Trek universe with its non-relativistic, non-Newtonian "subspace" underlying its seemingly Newtonian/relativistic normal space).

So again I'd say tractor beams are really mundane pieces of hardware, likely to be found on every ship in at least dozens if not hundreds of applications. That they aren't weaponized more is apparently because shields almost completely negate their grip... But the E-D having, say, a hundred and fifty emitters ranging from handheld to Stargazer-towing seems likely and logical.

It's not as if any Trek episode hinges on the heroes or the villains knocking out the one and only tractor beam emitter. They may knock out the beam that holds them captive, which is already plenty enough - other beams won't kick in quickly enough to matter. Or,. more commonly, they may overload the one beam holding them by overloading the enemy vessel's power systems, in which case she won't have enough oomph to fire up another beam even if there were sixty emitters remaining for the task.

Timo Saloniemi

I am sorry but how do lift, push or drag anything without a fulcrum of some kind? There are laws of physics in this universe, you know?

 

[Nebusj]

I am sorry but how do lift, push or drag anything without a fulcrum of some kind? There are laws of physics in this universe, you know?

They put laws of physics in the Trek universe? CURSE YOU J J ABRAMS!

 

[Kobayshi Maru]

I am sorry but how do lift, push or drag anything without a fulcrum of some kind? There are laws of physics in this universe, you know?

They put laws of physics in the Trek universe? CURSE YOU J J ABRAMS!

 

[Mytran]

Maybe the "grabbing" bit of the tractor beam is only a tiny part of it's function. Perhaps a large part of the glowy blue lines is to do with generating an antigravity field around the object, lowering its inertial mass to the point where it weighs virtually nothing?

 

[Kobayshi Maru]

Maybe the "grabbing" bit of the tractor beam is only a tiny part of it's function. Perhaps a large part of the glowy blue lines is to do with generating an antigravity field around the object, lowering its inertial mass to the point where it weighs virtually nothing?

Well, it didn't work in Cause And Effect.


Apparently, blowing off a little air was more effective.

 

[Mytran]

Maybe it takes time with larger objects? However, it is silly that the amount of air in that (relatively) tiny shuttlebay would have had any appreciable influence on redirecting such a massive ship.

 

[Timo]

Unless, of course, it was pushed out at a significant fraction of lightspeed.

Remember that while the ship was powerless, it still had gravity (which is another tech apparently almost completely independent of power). Data could have adjusted the direction and magnitude of gravity in the shuttlebay and spat out the air with immense force.

That's the thing about "laws of nature" in Trek: they very, very clearly are no longer in force. Newton is not only dead and buried, but also exhumed, drawn and quartered, cremated, shot to space, recovered, poured in concrete and dropped in the Marianas Trench. The one thing that has never applied to Trek is "every action has an equal and opposite reaction"... Tractor beam is one prime application of that, but things like impulse drive or onboard gravity also violate this principle that empirically does appear to be in force in our universe. Yet apparently, all it takes to discredit Newton is enough technology.

Timo Saloniemi

 

[Kobayshi Maru]

Maybe it takes time with larger objects? However, it is silly that the amount of air in that (relatively) tiny shuttlebay would have had any appreciable influence on redirecting such a massive ship.

I couldn't agree more.

 

[Kobayshi Maru]

Unless, of course, it was pushed out at a significant fraction of lightspeed.

Remember that while the ship was powerless, it still had gravity (which is another tech apparently almost completely independent of power). Data could have adjusted the direction and magnitude of gravity in the shuttlebay and spat out the air with immense force.

That's the thing about "laws of nature" in Trek: they very, very clearly are no longer in force. Newton is not only dead and buried, but also exhumed, drawn and quartered, cremated, shot to space, recovered, poured in concrete and dropped in the Marianas Trench. The one thing that has never applied to Trek is "every action has an equal and opposite reaction"... Tractor beam is one prime application of that, but things like impulse drive or onboard gravity also violate this principle that empirically does appear to be in force in our universe. Yet apparently, all it takes to discredit Newton is enough technology.

Timo Saloniemi

The speed of expulsion of a gas is determined by its temperature, in order to have a speed of a "significant fraction of light speed" the gas would have to be hotter than the innermost part of our Sun.

 

[Timo]

Umm, not in this case. The gas would not be expelled by virtue of its pressure - it would be dropped out of the bay like a lump of lead, only expanding after it had left the bay.

Timo Saloniemi

 

[Kobayshi Maru]

Umm, not in this case. The gas would not be expelled by virtue of its pressure - it would be dropped out of the bay like a lump of lead, only expanding after it had left the bay.

Timo Saloniemi

I am sorry but that doesn't make any sense.

 

[Timo]

I'm sorry if it doesn't, to you. But that's how it works: the gas in this scenario is not expelled because it wants to expand out of the bay, but because gravity suddenly points towards the door and has a value of something like a thousand or million gee or whatever.

This means that the total mass of the air m will be accelerated aft at a in one big lump, with a resulting force of F=ma, and (if Data doesn't hit any "Neutralize Newton" switches) an equal but opposite force on the starship. It doesn't have to expand or exhibit any other gas-like qualities (indeed, it probably doesn't have time to, before it finds itself in vacuum). It won't get hot before it reaches the vacuum, at which point the defining of its temperature becomes an interesting exercise in thermodynamic semantics. It will simply shoot out of the bay like a very high speed bullet.

Now, whether the kinetic energy of the air will be sufficient for giving the ship the kick she needs at any reasonable value of artificial gravity acceleration is a different question. But just like the gravity in the shuttlebay is variable, the mass of the starship herself is variable, or at least her inertia is.

We would have to find out whether the ship's inertia-manipulation fields are operational or not to decide whether she can suddenly decide to weigh all of forty-seven grams. Internal inertia-manipulation virtually never goes down (or else our heroes would be pulped on short notice as their ship shook, and rotated like a centrifuge with an arm a quarter of a mile long), but we have little evidence on what happens to external inertia when main power is lost.

The main point here is, Newton is optional for Star Trek, and necessarily so. If our heroes cleverly choose where to apply Newton and where not to, they can move entire moons with just one starship, or entire starships with one finger. And sometimes they do.

Timo Saloniemi

 

[Mytran]

Man, those little shuttlecrafts are tough, if a lump of air is rushing by them at that speed and temperature!

OTOH, if the mass reducing machinery of the ship is still operating, there would be no need to worry about this stuff - the weight of the air at normal pressure and speed would be enough to bump the ship once it left the field and returned to normal space.

 

[Timo]

The problem with assuming that ship mass reduction really is working is that the force of mere vented air is still feeble - so the ship ought to be very, very light in order to move, which in turn means the tap by the Bozeman should have sent the ship spinning, not exploding.

And shuttlecraft are tough. Why, don't spacecraft very much like that go to warp within atmospheres?

Timo Saloniemi

 

[Mytran]

After doing a quick rewatch of the episode, I noted the following:

• Upon reaching the anomaly, LaForge reports that all "main systems" have gone offline. This certainly includes thrusters and indeed all propulsion systems, as well as shields. Given all that, I'd be very surprised if the mass-reducing machinery (which would be tied to the engines very likely) is still operational.
• In the time that Data takes to speculate on the "3" message sent to himself and announce that he is choosing the shuttlebay option, Worf has already announced that he is activating the tractor beam. It may well be a combination of both methods that lead to overall success (the Bozeman's nacelle only just grazed the Enterprise's after all)

 

[Ghrakh]

(the Bozeman's nacelle only just grazed the Enterprise's after all)

Yes, meaning the Enterprise didn't need to move all that much. I never had a problem with the decompression accomplishing that.

The main point here is, Newton is optional for Star Trek

Perhaps, but the main shuttlebay is at the top of the saucer, above the ship's center of mass. So wouldn't the enterprise be pushed not only forward, but also down?

 

[Mytran]

Yes there is only grazing of the nacelle, but the final solution shows an appreciable gap between the two vessels, something that (IMO) would only be possible using a combination of Tractor Beam AND shuttlebay decompression.

 

[Mytran]

The problem with assuming that ship mass reduction really is working is that the force of mere vented air is still feeble - so the ship ought to be very, very light in order to move, which in turn means the tap by the Bozeman should have sent the ship spinning, not exploding.

Can't believe I missed this last night (well given that it was past midnight, maybe I can). Anyway, your statement presupposes that the ship is kept at a ridiculously low mass all the time. In this instance, the ship would only need to be lowered to 47 grams (or whatever) in order for Riker’s decompression plan to have a chance of success; beforehand (with the tractor beam plan) the ship would need to keep its mass at normal levels to act as an anchor for the beam.

Data does press an awful lot of buttons after all… (OK, I know that’s nothing special)

 

[Kobayshi Maru]

I'm sorry if it doesn't, to you. But that's how it works: the gas in this scenario is not expelled because it wants to expand out of the bay, but because gravity suddenly points towards the door and has a value of something like a thousand or million gee or whatever.

This means that the total mass of the air m will be accelerated aft at a in one big lump, with a resulting force of F=ma, and (if Data doesn't hit any "Neutralize Newton" switches) an equal but opposite force on the starship. It doesn't have to expand or exhibit any other gas-like qualities (indeed, it probably doesn't have time to, before it finds itself in vacuum). It won't get hot before it reaches the vacuum, at which point the defining of its temperature becomes an interesting exercise in thermodynamic semantics. It will simply shoot out of the bay like a very high speed bullet.

Now, whether the kinetic energy of the air will be sufficient for giving the ship the kick she needs at any reasonable value of artificial gravity acceleration is a different question. But just like the gravity in the shuttlebay is variable, the mass of the starship herself is variable, or at least her inertia is.

We would have to find out whether the ship's inertia-manipulation fields are operational or not to decide whether she can suddenly decide to weigh all of forty-seven grams. Internal inertia-manipulation virtually never goes down (or else our heroes would be pulped on short notice as their ship shook, and rotated like a centrifuge with an arm a quarter of a mile long), but we have little evidence on what happens to external inertia when main power is lost.

The main point here is, Newton is optional for Star Trek, and necessarily so. If our heroes cleverly choose where to apply Newton and where not to, they can move entire moons with just one starship, or entire starships with one finger. And sometimes they do.

Timo Saloniemi

I don't know where you get these kooky ideas but know that at its peak the gravity of the sun is less than 200 Gs in spite of its size. Anything the size of the shuttle-bay that would generate a field of one million Gs would become instantly a black hole.

 

[Timo]

Naah. The ship's impulse engines can make the ship go at a thousand gee or so (see e.g. ST:TMP) - this doesn't result in any black holes that we'd be told of.

Artificial gravity directionally applied (as it always is) to spit out air wouldn't collapse anything. It would just accelerate stuff away. Although why Data didn't choose to also accelerate those shuttles out of the bay, I don't know. They'd add to the expelled mass, and there'd be absolutely no harm to dumping them - even if shuttles weren't expendable (and they are - random 23rd century relics can have them as mementos!), they could easily be recovered after the ejection.

Timo Saloniemi